A move in the Senate to provide enhanced surveillance powers to the FBI through the use of National Security Letters met a hurdle Monday after Senator Ron Wyden placed a hold on the 2017 Intelligence Authorization bill over the controversial provisions.

Wyden’s hold is a a measure by which a senator or group of senators can prevent a motion from reaching a vote.

The 2017 Intelligence Authorization Act includes provisions to expand warrantless government surveillance and takes aim at a valuable independent oversight board, according to Wyden, a Democrat from Oregon, who last month voted against the bill in the Senate Select Committee on Intelligence.

The current version of the intelligence authorization bill contains a provision in section 803 that would authorize individual FBI field offices to demand Americans’ email and Internet records simply by issuing a NSL, without court oversight, Wyden said in a statement while announcing the hold in the Senate.

The FBI is currently allowed to issue NSLs to collect phone records and financial records, without the approval of a judge, and in 2013 the President’s surveillance review group recommended reforming this authority, to require court oversight such requests, Wyden said.

Wyden said he hoped to be able to work with colleagues to remove the controversial provisions prior to their consideration of the bill by the full Senate. “Until then I will object to the proposal to pass this bill by unanimous consent,” he added.